High-tension insulator.



S. BARFOED.

HIGH TENSION INSULATOR.

APPLICATION FILED AUG. 1a, 1914.

1,173,994.v Patented Feb. 29,1916.

2 SHEETS-SHflET I.

WITNESSES: IN VICNLOR S. BARFOED.

HIGH TENSION INSULAIOR. APPLICATION FILED AUG. 18, 1914.

1,173,994. Patented Feb. 29, 1916.

2 SHEETSSHEET 2.

WITNESSES: INUINTOI) UNITED STATES PATENT OFFICE.

SVEND BARFOED, OF OAKLAND, CALIFORNIA, ASSIGNOROF TWO-FIFTHS TO OTIS GIBSON, OF SAN FRANCISCO, CALIFORNIA.

HIGH-TENSION INSULATOR.

Specification of Letters Patent.

Application filed August 18, 1914. Serial No. 857,315.

To all whom z'tmay concern:

Be it known that I, Svnno BARFOED, a subject of the King of Denmark, residing at Oakland, in the county of Alameda and power with minimum size of line conductors.

-In the insulation of high potentials of sixty thousand to one hundred thousand volts and over, serious diiiiculties arise by reason of leakage or creepage of the electricity over the surface of the insulators. This creepage is principally due to dust and moisture upon the surface of the insulators, which constitutes a film for the conduction of electricity or minute conduct-- ing areas between which static discharges may take place. (A source of failure in the common type of high voltage insulators is due to minute hair-cracks in the porcelain or lass of the insulators. Electrically conuctive paths are fused through these cracks resultin in the destruction of the insulators.) hese cracks are caused by certain stresses set up in ordinary insulators by bolts and other types of fastening devices which are generally secured in the insulator by means of cement. The relative expan- $1011 of cement, iron and porcelain being quite dissimilar, naturally causes excessive strains within the insulator, producing the hair-like cracks.

The object of the present invent on is to rovide a form of insulator fastening, which I is so positioned and secured that'the temperature changes will not produce stress in the body of the insulator, thereby overcomin the difficulties previously mentioned.

' "ther objects will hereinafter appear.

Figure 1 shows the application of the mvention. Fig. 2 is a longitudinal section through the insulator. Fig. 3 1s a detail view of same showing the fastening means. Fig. 4 is a perspective view of the securing clip. Fig. 5 is a cross section on hne 5-5 of Fig.

A indicates an electric msulator whereby a wlre or conductor 2 may be suspended from the tower or post 3. The insulator proper consists of a spool or tube-shaped ody of suitable length constructed of porcelam or like material, having a plurality of deep annular parallel corrugations 5, and hlglrridges 6 formed on its exterior surface. The insulator proper is girdled centrally by a clamp 7, which may be fastened by a bolt or rivet 8, to the suspensionarm 9 of post or tower 3.

For thoroughly insulating high tension llnes, a plurality of insulators are suspended one from the other, as indicated in Fig. 1, this being accomplished by a central beam 10, which is secured at 11 in the center of each insulator tube, and upon the outer ends of beam are mounted suspension links 12, by which one other. i

' Suitably secured'to the center portion of beam 10 by means of a rivet 13, or the like, is a pair of clip members. These clip members are provided with four arms, 14, 15, 16 and 17, arms 14 and'15 being turned up as at 18, after the beam is inserted, to secure it in position within the insulator. Surrounding the beam and forming a packing or cushion between the interior of the insulator and the beam proper, is a lining of compressible fiber or like material. This fiber lining, is divided into two sections, 19 and 22, as indicated in Fig. 5, and this is held in position by arms 16 and 17 which extend into recesses 16 and 17 formed in the ends of the fiber sections.

The compressible lining interposed between the insulator and the beam 10, absorbs all stress caused by the difference in expansion between the iron beam and the insulator proper, thus relieving the insulator from stress of this nature. The fiber cushion, furthermore, absorbs all the me-' chanical force transmitted through it, so that only compressive stresses occur. The body of the insulator is thus entirely relieved of the stress produced by temperature changes and the difiiculties heretofore mentioned are thus entirely overcome.

The metal clips by which the beam is secured within the insulator, provide a means by which the insulators may be easily and quickly connected or disconnected as the case may be.

A compressible fiber lining 21 may be inserted between clamp 7 and the exterior of the insulator.

The material and finish of the several insulator is hung from the Having thus described my invention, what I claim and desire to secure by Letters Patent, is-

1. In a high potential insulator, a hollow insulating member, a beam extending through the insulator, a compressible lining interposed between the beam and the interior of the insulator, and clips secured to the beam having bendable arms formed thereon to secure the beam within the insulator. I I 2. In a high potential insulator, a hollow insulating member, a beam extending through the insulator, an annular seat formed within the insulator, a compressible lining interposed between the beamand said seat, and clip members secured to the beam having bendable arms formed thereon engageable with the sides of the annular seat to secure the beam within the insulator.

3. In a high potentialinsulator, a hollow insulating member, a beam extending through the insulator, and clips secured to the beam to secure the beam within the insulator.

4. In a high potential insulator, a hollow insulating member, a beam extending through the insulator, an annular seat formed within the insulator, a compressible lini-ng interposed between the beam and witnesses.

' lVitnesses said seat, clip members secured to the beam having bendable arms formed thereon enageable with the sides of the annular seat to ncure the beam within the insulator, and 'secondary arms on theflclips to secure the compressible lining in position.

5. In a high potential insulator, a tubillarv-shap'ed insulator, an annular comparatively narrow seat formed interiorly of the insulator, a beam extending through the insulator-{and a compressible lining inter posed between the annular seat and beam.

6. In a high potential insulator, a tubu lar-shaped insulator, an annular comparatively narrow seatformedinteriorly of the 7. In a high potential insulator, a tubu- I lar-shaped insulator, an annular comparailVGl) narrow seat formed interiorlyof the insulator, a beam extending through the insulator, a compressible lining interposed between the annular seat and beam, and means for securing the beam .and lining against endwise movement in the annular seat,said

means comprisingclip-like fingers secured on the beam and engageable with the sides.

of the annular'seat.

In testimony whereof I have hereunto setmy hand in the presence of two subscribing svnun BARFOED.

IRvINE 'SINXETT, IV. W. HEALEY. 

